Amino-Functionalized β-Cyclodextrin to Construct Green Metal–Organic Framework Materials for CO₂ Capture

Abstract

The adsorption of CO 2 by conventional liquid alkanolamine adsorbents does not meet the requirements for green-friendly development in industrial applications. In this work, we constructed NH 2 -β-CD-MOF for the first time through the amino-functionalization of the lowest-priced, readily available, and biocompatible β-CD. Subsequently, the samples were characterized by single-crystal X-ray diffraction, powder X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, elemental analysis, and N 2 adsorption/ desorption. The CO 2 adsorption capacity of NH 2 -β-CD-MOF was found to be 12.3 cm 3 /g, which is 10 times that of β-CD-MOF. In addition, NH 2 -β-CD-MOF has outstanding selective adsorption of CO 2 /N 2 (947.52) compared with the reported materials. The adsorption mechanism of CO 2 was analyzed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Furthermore, we have found that NH 2 -β-CD-MOF has better water stability relative to β-CD-MOF and γ-CD-MOF, and it can be recycled by an ultrasonic method.

Hierarchical porous carbon derived from green cyclodextrin metal‐organic framework and its application in microwave absorption

“…The preparation method was adjusted according to the method previously reported by our research group 18,27 . In detail, γ‐CD (648 mg, 0.5 mmol) and KOH (224 mg, 4 mmol) were dissolved into 15 ml of pure water, and then 5 ml of CH 3 OH was added to obtain a turbid liquid.…”

“…MOFs are three‐dimensional porous crystal materials, composed of metal ions and organic ligands. MOFs have many interesting features due to its unique crystal structure, including ultra‐low density, ultra‐high surface area, and adjustable porosity 17–19 . However, most MOF‐derived carbons contain mainly micropores so far and many MOF templates suffer from environmentally hazardous raw materials 7,8 .…”

“…Unlike other MOFs with single pore size, CD‐MOF has different pore sizes, including spherical cages, window pores and cavity of CD. The unique porous texture and inherent alkaline metal elements allow CD‐MOF showing great potential for porous carbon fabrication 18,20,21 . Actually Liu group 22,23 has prepared porous carbons using β‐CD‐MOF and γ‐CD‐MOF, respectively, and applied these CD‐MOF‐derived porous carbons as efficient pollutants adsorbent.…”

Applications of Metal-Organic Framework Materials

“…The adsorption of CO2 by traditional liquid alkanolamine adsorbent can not meet the requirements of green development in industrial applications. NH2-β-CD-MOF [9] was first constructed by an American company by amino-functionalizing β-CD, the cheapest, readily available and biocompatible form. The selective adsorption of NH2-β-CD-MOF on CO2/N2(947.52) is also better than that of existing materials.…”

Recent Advances of Porous Materials Based on Cyclodextrin

“…[ 34 ] Also, our group prepared NH 2 ‐ β ‐CD‐MOF to expand the CD‐MOF family by solvent evaporation method and ultrasonic methods. [ 35 ] The NH 2 ‐ β ‐CD‐MOF exhibited a regular hexagonal crystal composed of seven NH 2 ‐ β ‐CD units (with a bowl‐like pore: 6 Å) connected by potassium ions ( Figure ). The existence of amino groups made this new MOF more stable than β ‐CD‐MOF and γ ‐CD‐MOF.…”